Figure 7 : The GPCR NPR-22/Tachykinin 2 receptor (NK2R) functions as the FLP-7 receptor in the intestine.

From: A tachykinin-like neuroendocrine signalling axis couples central serotonin action and nutrient sensing with peripheral lipid metabolism

Figure 7

(a) Fat content of vehicle- and 5-HT-treated wild-type, npr-22 and frpr-3 animals fixed and stained with oil Red O was quantified. Fat content for each genotype is expressed as a proportion of fat retained upon 5-HT treatment±s.e.m. (lower panels; n=10-13). **P<0.01 and NS, not significant by two-way ANOVA. (b) Fluorescent image of a transgenic animal bearing an npr-22::GFP transgene under the control of the endogenous npr-22 promoter. GFP expression was observed in the intestine and several pairs of neurons in the head. A, anterior; P, posterior; V, ventral; D, dorsal. Scale bar, 50 μm. (c) Fat content of vehicle- and 5-HT-treated wild-type animals and npr-22 mutants fixed and stained with oil Red O was quantified, and is indicated as a proportion of fat retained upon 5-HT treatment. For the transgenic lines bearing npr-22 expression, the promoters used are indicated, and non-transgenic animals are marked as (−) and transgenic animals as (+). The unc-31 promoter was used for expression in neurons and the ges-1 promoter was used for expression in the intestine. Data are expressed as a proportion of fat retained upon 5-HT treatment±s.e.m. (lower panels; n=8–12). *P<0.05 and **P<0.01 by two-way ANOVA. (d) The fluorescence intensity of atgl-1 expression in vehicle- and 5-HT-treated wild-type animals and npr-22 and flp-7;npr-22 mutants bearing an integrated atgl-1::GFP transgene was quantified. The fluorescence intensity is expressed as a percentage of vehicle-treated wild-type animals±s.e.m. (n=17–25). **P<0.01 and ns, not significant by two-way ANOVA. (e) Wild-type animals and npr-22 mutants bearing the flp-7 over-expression (OX) transgene were grown on plates containing either vehicle (10% dimethyl sulfoxide) or the selective NK2R antagonist GR159897 at the indicated concentration. At the completion of development (late L4 stage), animals were transferred to plates containing GR159897 and either vehicle or 5-HT. Fat content was quantified for each condition and is expressed as a percentage of vehicle-treated wild-type animals±s.e.m. (11–20). *P<0.05, **P<0.01, ***P<0.001 and NS, not significant by two-way ANOVA.